Think of a database system that interests you, it could be the card shop inventory system from the previous competency. It can be one you interact with everyday in your profession, a hobby, or one that you would like to have exist as a system.
Your assignment is to submit a design for a relational database using a relationship or chart modeling tool such as Lucidchart. Your assignment will be easier to complete if you do the initial design work for you database on paper. The design is an iterative process that is likely to have stops and starts along the path to a final design. When your design is finalized, then it is time to move on to depicting your database electronically. This is a lucidchart tutorial that will help you with database design. Your final designs should bear some resemblance to this mail order shipping system relational database screenshot. Additional examples of actual relational databases are available here.